The present invention relates to a circulation system for a body of liquid. More specifically, to a floating system for exchanging or displacing water or other liquids from lower levels and delivering them to the upper surface to allow for maximum exposure to the atmosphere.
In order for many bodies of water to develop and maintain a healthy eco-system, a non-specific amount of circulation is typically required. This is because the bacteria necessary for breaking down or digesting nutrients is immobile, and therefore, needs to be placed in intimate contact with nutrients, necessary to thrive, by circulation of the water. Furthermore, in the majority of applications, bacteria also needs oxygen to survive and flourish. The most readily available source of oxygen is from the atmosphere.
Oxygen can enter the water through contact with the atmosphere which may be accelerated through mixing, as happens in nature through waterfalls, streams, rain, and wind. It has been found that adding artificial aeration, to assist nature, to natural and man made ponds and lagoons can greatly increase the health of the ponds. This may be especially useful in sewage lagoons and the like as the decay process could be accelerated and unpleasant smells reduced.
In order to combine the movement of liquid and supplying of the oxygen, past prior art has typically used one of three methods: (1) a surface splashing action (2) an aspirator/boat prop effect which draws atmospheric air in and then forces air bubbles out or (3) compressing atmospheric air and then releasing it at the bottom of the body of liquid. In each of these actions two things are readily apparent (A) high energy input with corresponding high maintenance needs and (B) the action created is always turbulent.
The use of pond aerators on floating bases has been well established such as those shown by U.S. Pat. No. 4,179,243 granted to Aide and U.S. Pat. No. 4,030,859 granted to Henager. In these patents, devices are typically supplied with a draft tube placed just below the surface of the water. This tube houses a propeller or impeller that is connected to a drive means. A draft line is placed at a predetermined depth and connected to the draft tube. Thus, as the drive means turns, the impeller or propeller draws water from a certain depth and defuses it at the water surface. This process circulates and turns the water in the pond. As power to the pump can be a significant issue in remote areas, such as the middle of a pond or lake, the efficiency of the whole unit is crucial to its success. This has required that alternative means of driving the pump on pond mixers would be desirable. One solution has been to use wind power, however wind powered pumps are large in size, expensive, cumbersome, and create a need for complex and expensive anchoring systems.
From this discussion it can be seen that a low energy, circulation method is needed. Such a method or device should be designed to gently circulate (vs. turbulent mixing) a liquid from bottom-to-top with a minimum amount of energy and deliver that liquid to a major oxygen source (the atmosphere) in a manner which will maximize atmospheric absorption. Further it would be advantageous to make such a system so that it can be driven by an inexpensive renewable resource, and thus, able to be used in remote areas with a minimal amount of setup.
It is the primary objective of the present invention to provide a method of circulating bodies of water in a highly efficient manner that allows for the use of an extremely low horsepower pump.
It is an additional objective of the present invention to provide a method of circulating bodies of water and thus, increase their exposure to the atmosphere through the use of an alternative source of power, such as relatively small solar panels.
It is a further objective of the present invention to combine these characteristics in a small, floating, portable device that can be placed in a desired location and left to circulate a liquid from a lower elevation to the surface.
It is a still further objective of the present invention to provide a method of delivering liquid, through a distribution dish or diffusor, in a non-turbulent manner that will maximize the amount of time the liquid remains on the surface.
These objectives are accomplished by the use of a floating circulation apparatus that has as an on-board power system consisting of a plurality of solar panels that produce the entirety of the power required to drive the water pump. This circulation device is equipped with a water impeller that is larger than, and tightly fitted over, the top of the draft tube through which the water from the pond or reservoir is drawn. By placing the impeller above and out of the draft tube, the efficiency of the pump will be greatly increased. Thus, the same amount of horsepower will move a much larger amount of liquid.
By having the impeller up and out of the draft tube, it is also possible to impart movement to the water in two different ways. First, the impeller moves water by a lifting action which is caused by the rotation of the auger-like impeller. Second, the impeller imparts a rotating motion to the water. This rotating motion will generate centrifugal force, causing even more water movement or mixing. Prior art circulation devices place the impeller down in the draft tube and thus, the rotating motion of the water is wasted as the water is trapped by the walls of the draft tube.
The present invention is also equipped with a large flow distribution or diffuser dish surrounding the impeller. The size and shape of the impeller works to allow the water to move directly away from the impeller, radially. Additionally, the flow diffuser is also equipped with a specially designed outer edge which does not impede the radial flow of water created by the impeller as it passes from the diffuser to the surface of the lake or pond. This allows the present invention to circulate a body of water more effectively, as the motion imparted to the water by the impeller is more efficiently passed outside of the diffuser. Thus, the centrifugal force phenomenon is utilized to create water movement at the surface which in turn operates to circulate the body of water.